Twin volute pump



July 10, 1962 H. c. ATWOOD, JR., ETAL 3,043,229

TWIN VOLUTE PUMP Original Filed May 27, 1957 H u BERT QATWOOD TR;

JOHN G.W|LL|AM5 IN V EN TORS United States Patent 3,043,229 TWIN VOLUTEPUMP Hubert C. Atwood, In, Westfield, and John G. Williams,

Springfield, N.J., a'ssignors to Worthington Corporation, Harrison,N.J., a corporation of Delaware Original application May 27, 1957, Ser.No. 661,656, now Patent No. 2,955,540, dated Oct. 11, 1960. Divided andthis application May 9, 1960, Ser. No. 27,914

2 Claims. (Cl. 103-103) Walled casings, but the splitter should remainthin for hydraulic reasons, and cost of metal involved.

In order to effectively cast a twin volute pump casing, it is imperativethat the thickness of the casing and the splitter be substantiallyequal; the equality in thickness being necessary to prevent flaws in thecasting, which flaws occur because of the unequal cooling time in arespective heavy casing and thin splitter cast integral therewith.

Casting the splitter as an integral part of the twin volute pump casingfor a high pressure application presents other difiiculties; forexample, twin volute pumps for high pressure applications undergorigorous inspection tests such as a radiographic examination of thecasting to determine whether there are flaws therein, searching throughtwo separate layers of metal, as is the case in a twin volute having anintegral splitter, not only detracts from the etficacy of the test, butalso adds to the expense of such inspection.

In many cases the integral splitter fails during hydrostatic leak test.Failure results from the weakness in the casting at the point where thethin splitter joins the heavy walled volute.

Flaws detected during inspection of the casting are usually repaired, bya manner well known in the art. Howeventhe flaws so detected, due to theinaccessibility of certain portions of the casing which results from thesplitter being cast integral therewith, sometimes cannot be repaired andas a consequence the casting is discarded.

Some installations require volute pumps capable of contending withextremely high pressures and, in addition, require a higher finish onthe inner periphery of the casing, which finish cannot be obtained bythe usual casting methods nor can the inner periphery of the volutecasing having a splitter integral therewith be finished by other wellknown methods in the art.

Accordingly, it is an object of the present invention to obviate theforegoing difiiculties in the manufacture of heavy walled twin volutepumps.

It is another object of this invention to locate the splitter accuratelyand connect it securely to the pump casing.

With these and other objects in view, as may appear from theaccompanying specification, the invention consists of various featuresof construction and combination of parts, which will be first describedin connection with the accompanying drawings.

FIGURE 1 is a longitudinal section showing a twin volute pumpconstruction embodying the principles of this invention.

FIGURE 2 is a section taken on line 22 of FIG- URE 1.

Referring more particularly to the drawings,.FIGUR E 1 shows thepreferred form of, the heavy walled twm volute pump comprising a volutecasing 1 of unitary construction, characterized by its spiral orscroll-like conformation and further provided with heavy walls generallydesignated 2 having an opening 20 communicating with chamber 21, inwhich an impeller 3 is rotatably mounted for pumping the liquid, fromthe axial Sucti inlet 4, formed in the front wall thereof, throughdischarge outlet 5.

One manner of associating the bootlike splitter is shown and it is notintended to limit the invention to this construction as other methods ofassociation will be readily apparent to those skilled in the art.Thusly, the bootlike splitter 8 is shown as having side walls 11 and 12which provide a U-shaped configuration and coact with the. casing todivide flow passingthrough the volute into the substantially equal flowpassages 6 and 7. a

An opening 22 is formed by the portion of the stripper disposed adjacentthe suction inlet 4 and an opening 23 is formed by the portion ofstripper 8 disposed adjacent opening 20 in the rear wall of the casing.It will be evident that opening 20 is formed, as shown in the drawings,to permit easy insertion and disposition of stripper 8 in operativeposition. The suction inlet 4 and openings 20, 22 and 23 are shown as inaxial alignment which facilitates assembly of the components of thepump.

Locater means taking the form of tapped holes 9 and drilled holes 10 areprovided respectively in the walls of the casing 1 and accommodate thesplitter in operable position.

In assembly the splitter 8 is disposed so that the walls 11 and 12thereof are contiguous to the walls 13 and 14 of the casing and openings17 in wall 11 are aligned with the tapped holes 9. Similarly tappedholes 15 in Wall 12 are aligned with drilled holes 10. Bolt means 16 maythen be inserted to connect the splitter 8 to the walls of the casing asabove described to divide the volute casing 1 into two substantiallyequal portions.

With the provision of a separate splitter element applicant discloses atwin volute pump that is characterized by the substantial minimizationof the problems hereinbefore mentioned. -It will be understood that theinvention is not to be limited to the specific construction orarrangement of parts shown, but that these may be widely modified withinthe invention defined by the claims.

What is claimed is:

'1. In a centrifugal pump of the twin volute type, a heavy walled casingof unitary cast construction having a front wall including a suctioninlet, said casing including a peripheral wall having a dischargeoutlet, said heavy walled casing including a rear wall spaced from saidfront wall, said rear wall defining an opening in axial alignment withsaid suction inlet, impeller means disposed through the opening in saidrear wall and being mounted in said casing for moving fluid from saidsuction inlet through said discharge outlet, an independent splitterelement adapted for insertion as a unit through the opening in theopening defined by the rear wall of said casing and said independentsplitter element including spaced side walls detachably mounted in saidcasing so that said spaced side walls are respectively contiguous withthe front and rear walls of said heavy walled casing, said independentsplitter element dividing the flow through said casing into twosubstantially equal portions prior to discharge, said independentsplitter element of constant width and of lesser wall thickness thansaid heavy walled casing, first and second locater means on the interiorportions of the front and rear walls of said casing, the side walls ofsaid splitter element respectively disposed in abutment with both of thelocater means, and means for rigidly detachab'ly connecting the splitterto said locater means to'maintain the splitter in operable position. a

2; In a centrifugal pump of the -twin volute type; a

heavy walled casing of unitary cast construction having a front wallincludinga suction inlet, said casing include ing a, peripheral wallhavinga discharge outlet, said casing including a rear wall spaced fromsaid front wall, said' rear wall defining an opening inaxial alignmentwith said suction inlet, impeller means disposed through the opening insaid rearwall and 'being mounted in said casing for moving fluid fromsaid suction inlet to said ing defined by the rear wall of said casingand said independent splitter element including spaced side wallsdetachahly mounted in said casing so that said spaced side walls arerespectively contiguous with the front and rear walls of said heavywalled casing, said independent split-,-

of tapped holes in the wall of the casing having said 25 suction inlet,a plurality of openings in the rear Wall of said casing, a plurality ofopenings in the periphery of the side wall of said independent'splittercontiguous V, to the front wall of said casing, tapped holes in theperiphery of the side wall of said independent splitter contiguous tosaid rear wall, the openings in the side wall disposed to coincide withthe tapped holes in the Wall of said casing and the tapped holes in theother side wall ofthe splitter disposed to coincide with the holes inthe rear wall of the casing, and threaded members rigidlydetachably'connecting the side walls of said spli ter in abutment withthe inner portion of the front and rear walls of said casing at thetapped holes and openingsto maintain the splitter in operative position.

discharge outlet, an independent splitterie lement adapted for insertionas a unit. through the openingin the open- 15 References Citediin thefile of this patent W UNITEDSTATES PATENTS, a 717,096 Harris Dec. 30,1902 931,636 Neumann Aug. 17, 1909 1,390,391 Skidmore 'Sept. 13, 19211,745,854 Lawaczeck Feb. 4, 1930 2,042,550 Putter -4. June 2, 19362,399,548 V Ingersoll Apr. 30, 1946 2,661,698 Schellens Dec. 8, 1953 5,7 ,F OR EIGNVPATENT S 170,815 Great Britain Oct. 14, 1921 1943 556,853Great Britain Oct. 25,

